Signal Technology Arizona Space Center Delivers HESSI Spacecraft Power Converters.

DANVERS, Mass.--(BUSINESS WIRE)--March 30, 1999--Signal Technology Corp. (AMEX:STZ) Tuesday announced that its Arizona Space Center has successfully completed the design and delivery of flight units for High Energy Solar Spectroscopic Imager (HESSI), selected for the next primary mission in NASA's Small Explorer series of space science missions.

Commented Gene L. Joles, president of Signal Technology's Arizona Space Center: "We are excited about our participation with Spectrum Astro on the HESSI program. Spectrum Astro will integrate our converters into the spacecraft bus, which they are developing for the University of California at Berkeley and NASA's Small Explorer Program.

"We appreciate the opportunity Spectrum Astro's team and their president, Dave Thompson, has given Signal Technology Arizona Operation & Space Center to participate in this project, and we look forward to supporting Spectrum Astro on other space assignments."

The HESSI mission will use a sun-pointed spin-stabilized spacecraft to investigate the physics of particle acceleration and energy release in solar flares, observing X-ray and gamma ray emissions with an unprecedented combination of high-resolution imaging and spectroscopy.

UC Berkeley, the prime contractor, is developing the HESSI payload as well as providing the lead for the science investigation team, which will include scientists from the United States, Switzerland, France, Japan, the United Kingdom and the Netherlands.

Spectrum Astro is performing the design and development of the spacecraft bus and will work with UC Berkeley to integrate and test the HESSI payload. HESSI is scheduled to launch aboard a SELVS II rocket in July 2000 during an anticipated period of high solar activity.

Signal Technology's Arizona Operation & Space Center has designed and manufactured DC-to-DC power converters, power control and conversion assemblies, and microwave frequency sources and subassemblies for programs such as IRIDIUM, Milstar II, NEAR, MSX, GPS IIF, SPACE STATION FREEDOM, SBIRS Low, TEMPO, MABUHYSAT and other commercial and military satellites.

Signal Technology designs and produces sophisticated, state-of- the-art electronic components and systems for a variety of defense, space and communication applications, including communications networks, satellite communications, electronic countermeasures, intelligence and guidance systems.

For further information about Signal Technology, visit the company's Web site at http://www.sigtech.com. Information about Arizona Operation & Space Center products and capabilities can be found at the division's Web site: http://www.sigtech.com/Arizona/index.htm.

"Safe-harbor" statement under the Private Securities Litigation Reform Act of 1995: The statements made in this news release that are not historical facts contain forward-looking information that involves risks and uncertainties. Important factors that may cause actual results to differ include but are not limited to market acceptance risks, the effect of economic conditions, the impact of competitive products and pricing, product development, capacity, supply constraints, and other risks detailed from time to time in the company's Securities and Exchange Commission filings. Signal Technology Corp. assumes no obligation to update the information included in this news release.